Apparatus for grooving and folding sheet material

ABSTRACT

THIS INVENTION RELATES TO AN APPARATUS FOR GROOVING AND FOLDING SHEET MATERIAL, ESPECIALLY PAPER SHEETS, BY MEANS OF ALTERNATELY ENGAGING GROOVING BARS AND GROOVING RECESSES ON TWO ROLLERS ROTATABLE IN OPPOSITE DIRECTIONS, EACH OF THE ROLLERS HAVING LONGITUDINAL GROOVING BARS THEREON AND LONGITUDINAL GROOVING RECESSES THEREIN WHICH PERPENDICULARLY INTERSECT ON EACH ROLLER WITH A TRANSVERSE GROOVING BAR AND A TRANSVERSE GROOVING RECESS, AND INCLUDING A RECEPTABLE FOR ZIGZAG-FOLDING AND COLLECTING THE FOLDED SHEETS.

March 16, 1971 F. RETTIG APPARATUS FOR GROOVING AND FOLDING SHEET MATERIAL Filed Feb. 5, 1969 FIG. I

I FIG. 2

R E mR N CL V I NR D CL R F H64 BY 33 1 1312M ATTORNEYS United States Patent Office 3,57%,841 Patented Mar. 16, 1971 3,570,841 APPARATUS FOR GRUOVING AND FOLDING SHEET MATERIAL Friedrich Rettig, Darmstadt, Germany, assignor to Kalle Aktiengesellschaft, Wiesbaden-Biebrich, Germany Filed Feb. 3, 1969, Ser. No. 796,066 Claims priority, application Germany, Feb. 2, 1968, P 16 11 375.0 lint. Cl. B65l1 45/20 U.S. Cl. 27073 9 Claims ABSTRACT OF THE DISCLOSURE This invention relates to an apparatus for grooving and folding sheet material, preferably paper sheets, by means of alternately engaging grooving bars and grooving recesses on two rollers rotating in opposite directions.

A known apparatus of this type is used for grooving and folding continuously conveyed endless paper webs. The known apparatus provides the paper web with transverse grooves about which the paper is folded in a zigzag form for the purpose of stacking. The grooving apparatus includes two rollers rotating in opposite directions and each having at least one concentric transverse grooving bar and one concentric transverse grooving recess at the same angular distance from each other. The grooving bars and recesses are so oriented to one another on both rollers that, during one revolution of each roller, the paper web is provided with at least two grooves which alternately project upwardly and downwardly.

For satisfactorily folding the endless paper web, special auxiliary devices are provided. By means of a known auxiliary device which, after grooving and during further revolution of the rollers, still holds the paper in the recess for a certain time, the paper can be deposited, when the web is guided in a vertically downward direction, in an open rectangular container below the rollers, with the formation of zigzag folds. The axes of rotation of the rollers are mounted parallel side-by-side in a horizontal plane. It is also known to mount the axes of rotation of the rollers one above the other and to pass the paper web to the rollers in a horizontal direction. In this case, the paper is passed behind the rollers in a horizontal guiding device. In the guiding device, the folds are formed, which lean against retarding plates, and, in the compressed state, move away from the rollers.

A special problem is the folding of loose sheets in two directions perpendicular to each other. This problem cannot be solved by the known apparatus.

The present invention provides an apparatus for grooving and folding individual sheets discontinnously conveyed to the apparatus, which sheets are to be provided with longitudinal and transverse grooved lines running perpendicularly to one another, whereupon each sheet is to be folded in a zigzag form along the grooved lines running parallel to one another.

This is achieved by longitudinal grooving bars and longitudinal grooving recesses which are perpendicularly intersected on the same rollers by at least one transverse grooving bar and at least one transverse grooving recess.

The apparatus includes a receptacle for zigzag-folding and collecting the folded sheets.

It has to be noted that the words longitudinal and transverse are employed in the present specification as referring to the travel direction of the paper sheet.

For ensuring trouble-free conveyance of the paper between the rollers and eliminating tearing of the paper, an advantageous modification of the invention provides that the distance of the rollers from each other in a small area at one end thereof, advantageously at the drive end, is smaller than the thickness of the paper to be processed and, in the other areas, approximately corresponds to the paper thickness. Further, the distances of the ends of the longitudinal grooving bars, leaving the original position of the rollers and first impinging upon the paper, from the transverse grooving recesses or transverse grooving bars increase from the small distance area towards the other end of the rollers.

In the case of conventional photoprinting papers, according to another advantageous characteristic of the invention, the distance of the first longitudinal grooving bar from the transverse grooving recess may be zero with the distances of the ends of the following longitudinal grooving bars increasing.

The invention provides advantageous shapes of the bars and recesses, which advantageously have triangular crosssections and engage one another without contact. This characteristic of the invention results in gentle treatment of the paper.

Further characteristics of the invention are the particularly simple and advantageous arrangements of the individual parts of the apparatus. The invention provides that the axes of the rollers are mounted one above the other, preferably vertically one above the other, that a horizontal table for feeding the paper and having a vertical holding bar extending normal to the roller axes at the end of the smaller roller distance is mounted in front of the rollers, and the receptacle is mounted behind the rollers.

The receptacle which represents a part of the apparatus according to the invention has a simple construction. The receptacle is a trough open at the top and at the front sides and extending parallel to the rollers, the bottom of which trough is slightly below the deepest point of the lower roller, its side wall adjacent the rollers ends slightly below the axis of rotation of the lower roller, its opposite side Wall ends above the gap of both rollers, and its width is somewhat greater than the distance of the transverse grooves.

The invention will be further illustrated by reference to the accompanying drawings, in which FIG. 1 is a rear view in elevation of the apparatus without the receptacle,

FIG. '2 is a sectional view of the apparatus taken along the line II of FIG. 1 showing the receptacle behind the apparatus and the sheet feeding device in front of the apparatus,

FIG. 3 is a similar sectional view of the apparatus as in FIG. 2, but showing the rollers in their initial positions, and

FIG. 4 shows a sheet folded by means of the transverse and longitudinal grooves.

In a frame 1, two rollers 4 and 5 are rotatably mounted about two parallel axes 2 and 3 mounted one above the other. The lower axis, directly driven by means of the crank 6, causes rotation of the upper axis and thus of the upper roller through the gear wheels 7. Due to the action of the gear-wheel transmission, both rollers rotate oppositely to one another in the directions indicated by the arrows in FIGS. 2 and 3.

At certain points on the rollers 4 and *5, the bars 8, 9, and 10 to 15 project from the surfaces. The bars engage recesses 16, 17 and 19 to 24 which are incorporated in the opposite surfaces. As can be seen from FIGS. 1, 2, and 3, the bars and recesses have triangular cross-sections, which have proved advantageous and gentle for use with paper, particularly for photoprinting paper. It is furthermore advantageous for the bars not to completely engage the recesses, i.e. contact-free engagement occurs between the bars and the recesses, which can be observed very distinctly in FIGS. 1 and 3 in that one can look through the engagement points between the bars and the recesses.

When sheet material other than photoprinting paper is processed with the apparatus of the invention, the bars and recesses may have cross-sections other than triangular, in which case contact-free engagement of bars and recesses may be partially or entirely dispensed with.

Each of the two rollers has a conventional transverse grooving bar and a transverse grooving recess. The rollers additionally are provided with longitudinal grooving bars and longitudinal grooving recesses, which perpendicularly intersect the transverse grooving bars and transverse grooving recesses. The upper roller 4 has a transverse grooving bar 8 and a transverse grooving recess 16. The bar and the recess are positioned with respect to one another at a distance of 180. The upper roller also has longitudinal grooving bars 10, 11, and 12 and longitudinal grooving recesses 19, 20, and 21. Each longitudinal grooving bar and longitudinal recess extends over only half of the periphery of the roller, i.e. from the transverse grooving bar to the transverse grooving recess. Viewed in the direction of the axis, a longitudinal grooving bar alternates with a longitudinal grooving recess. On the lower roller, the transverse grooving bar is indicated by the numeral 9 and the transverse grooving recess by numeral 17. correspondingly to the upper roller, the lower roller has three longitudinal grooving bars 13, 14, and 15, and three longitudinal grooving recesses 22, 23, and 24. Each grooving bar on the upper roller forms an engaging pair with a grooving recess of the lower roller, and vice versa.

By means of the gear Wheels 7, the upper and lower rollers are connected to one another as is shown in FIGS. 1 to 3. In the initial position of the rollers according to FIG. 3, the transverse grooving bar 8 of the upper roller engages the transverse grooving recess 17 of the lower roller. A paper sheet 25, conveyed on a horizontal table 26, is pushed between the rollers.

A holding bar 27 projecting at the drive end vertically upward from the horizontal table and extending normal to the roller axes serves as the side guiding means for the paper sheet. Each paper sheet is so placed into the apparatus that, after half a revolution of the crank 6 or of each roller 4 and 5, the first transverse groove is pressed into the paper in an upward direction by pressing the transverse grooving bar 9 into the transverse grooving recess 16.

In order to ensure free advance of the paper parallel to its longitudinal edges, the paper sheet is not gripped by the rollers over its entire width. For this purpose, there is a free space between the rollers which approximately corresponds to the thickness of the paper to be processed. As shown in FIG. 1, the free space extends as a longitudinal gap 28 between the rollers to a point adjacent the drive end. In the small areas of greater diameter 29 and 30, the distance of the rollers from each other is less than the thickness of the paper to be processed. As soon as the revolution of the rollers begins, the paper is gripped between the areas of greater diameter. At the same time, the longitudinal grooving bars 13, 12, and 14 impinge upon the paper, i.e. the lower longitudinal grooving bars 13 and 14 with their lower ends adjacent the lower transverse grooving recess 17 and the longitudinal grooving bar 12 with its upper end adjacent the upper transverse grooving bar 8. Simultaneously passing the ends of the three longitudinal bars 13, 12,

and 14 into the paper would lead to tearing of the paper in the direction of the longitudinal grooves, particularly at their intersecting points with the transverse grooves. In order to overcome this drawback, the invention provides that the longitudinal grooving bars are successively pressed into the paper in the sequence 13, 12, and 14. For this purpose, the distances of the ends of the longitudinal grooving bars increase from the transverse grooving recess or transverse grooving bar from the drive end to the other end of the rollers. These distances are indicated in FIG. 1 in sequence by 31, 32, and 33. When processing conventional photoprinting paper, the distance 31 may be zero, as is shown in FIG. 1. The distances 32 and 33 distinctly increase from the left to the right-hand side. With other papers or other sheet material, the first distance 31 also may be different from zero.

The article produced with the apparatus of the invention upon leaving the rollers is a paper sheet having transverse and longitudinal grooves and being zigzag folded about the parallel grooves, and deposited as a package with superposed folds before discharge from the apparatus.

The sheet shown in perspective view in FIG. 4 has the transverse grooves 34 and longitudinal grooves 35. The sheet has been automatically folded in the apparatus along the transverse grooves. Folding along the longitudinal grooves is performed by hand outside the apparatus.

In order to enable folding about the transverse grooves within the apparatus, a receptacle 36 is positioned behind the rollers. The receptacle has the form of a trough, open at the top and at the front sides, which extends parallel to the rollers and the bottom 37 of which is slightly below the deepest point of the lower roller. A small side wall 38 adjacent the rollers ends slightly below the axis of rotation 3 of the lower roller 5. A large side wall 39 opposite to the small wall ends above the gap between both rollers. The width of the trough is somewhat larger than the distance of the transverse grooves.

As can be seen in FIG. 2, the receptacle has such an action that the sheet leaving the rollers and provided with grooves is zigzag-folded about the grooved lines 34 when impinging upon the side wall 39. Due to the force of gravity, the folded sheet 40 descends and is collected at the bottom of the receptacle with the formation of a package.

It will be obvious to those skilled in the art that many modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.

What is claimed is:

1. An apparatus for grooving and folding sheet material which comprises a pair of rollers rotatable in opposite directions, each of said rollers having longitudinal grooving bars thereon and longitudinal grooving recesses therein for grooving the sheet material in the direction of travel thereof, said bars and recesses perpendicularly intersecting on each roller with at least one transverse grooving bar and at least one transverse grooving recess for grooving the sheet material normal to the direction of travel thereof, means for feeding the sheet material between the rollers, and receptacle means for zigzag-folding the sheet material about the grooved lines normal to the direction of travel thereof and for collecting the folded sheets.

2. An apparatus according to claim 1 in which the rollers are spaced from each other in a small area at one end by a distance less than the thickness of a paper to be processed, and, over the remainder of the length of the rollers, they are spaced by a distance approximately equal to said thickness.

3. An apparatus according to claim 1 in which the distances of the ends of the longitudinal grooving bars, leaving an original position of the rollers and first impinging upon a sheet material from a transverse groov- 5 ing recess or transverse grooving bar. increase from one end to the other end of the rollers.

4. An apparatus according to claim 3 in which the distance of the end of a first longitudinal grooving bar from a transverse grooving recess is zero, and the distances of the ends of successive longitudinal grooving bars progressively increase.

'5. An apparatus according to claim 1 in which the grooving bars and grooving recesses have triangular crosssections and engage each other without contact.

6. An apparatus according to claim 1 in which the rollers are mounted one above the other.

7. An apparatus according to claim :6 in which the receptacle means is a trough the bottom of which is slightly below the lowest point of the lower roller, a Wall adjacent the rollers terminates slightly below the axis of rotation of said lower roller, and the opposite wall terminates above a gap between the rollers and References Cited UNITED STATES PATENTS 1,365,947 1/1921 Overbury 270-61X JEROME SCHNALL, Primary Examiner P. V. WILLIAMS, Assistant Examiner US. Cl. X.R. 270-64 

